M1

DATA

Tbc Girling hydraulically operated braking system employs disc type brakes on the front wheels and brake shoes on the rear wheels. The rear brake shoes are of the slidiing type and incorporate the lever handbrake mechanism.

Make - Girling

Type: Front: Disc

Rear : Sliding Shoe

Pedal Free Movement – 1/4 in. approx.

Handbrake . Pull-up type

Handbrake Operation – Mechanically on rear

Total Braking Area - 301 sq. in.

Diameter of Discs. 11 inches

Inside Diameter of Drum : Front 10-1/2 in. Rear 9 in

Shoe lining - Width 1-3/4 in.

M2

INSTALLATION OF BRAKES

The brakes on all four wheels are hydraulically operated by foot pedal application, directly coupled to a cental valve type of master cylinder. The master cylinder includes a reservoir in which the brake fluid operating pressure is originated. The associated system coconsists of metal piping, flexibie hose and unions. On depressing the brake pedal, liquid is pressed trough the system to the front ind rear brakes via a five-way union. At each front wheel fluid is delivered to the caliper unit where a two-way union drives the fluid to the rear of the brake pads forcing them outwards against the disc. From the five-way union to a single pipe carries oil to the two-way union, mounted on the rear axle, which passes the fluid to a brake cylinder on each wheel. The cylinder piston is forced outwards to operate the front and trailing brake shoes. When the foot pedal is released, springs return the front wheel caliper pads and the rear wheel brike shoes to their normal position. A mechanical linkage actuated by the hand lever operates levers located on the rear wheel back plates to operate the brake shoes independently of the hydraulic braking system.

M3

GENERAL INSTRUCTIONS

Absolute cleanliness must be observed when dismantling any part of the braking system. All road dirt must he removed and the brake components disantled on a bench covered with clean paper sheets; any internal hydraulic

parts or rubber seals should not be handled with greasy hands or rags. Do not wash units in petrol, paraffin or trichlorethylene, these fluids cause damage to rubber parts. All internal metal parts should be washed in a tray of clean brake fluid. dried with clean dry lint-free cloth and laid out in assembly order on clean paper. Examine all rubber parts carefully for signs of 'sponginess' or perishing and renew if necessary, soaking the new parts in brake fluid before assembly. Main castings may be cleaned in nornal cleaning fluid and dried with clean dry lint-free cloth and a jet of clean dry air. After cleaning and inspection parts are to be dipped in clean brake fluid and assembled wet to aid lubrication.

Stop light Switch

The hydraulically operated stop switch is fitted to the five-way union. The union distributes hydraulic oil from the master cylinder to the four wheels and is bolted to the forward left hand side of the chassis.

M4

HANDBRAKE

The handbrake system, to the rear wheels only, operates from a pull-on lever situated hetween the driver's seat and the propeller shaft tunnel. The brake lever is secured by two bolts and nuts to a special bracket welded to the chassis. The cabine assembly, consisting of an outer case and inner cable. leads from the lever to a yoke near the rear axle. From the yoke the cable leads to the rear ofside wheel, (right hand drive) or to the rear near side wheel (.1eft liane] drive). On both drives a transverse cable leads from the yoke to each rear wheel. A grease nipple is located on the underside of the outer case.

Removal and Assembly of handbrake Cables

To remove the trztiisverse cabine. disconneet cable elevis pin by reiiioving elevis pin frons brake cable yoke. remove elevis fro!ii wheel brake Fit ncw cable "tssenibly. cable sluck can be taken tip on the adjustiii£ nut at tbreaded end of c"thie. Eiistire tliat loek nut is fiilly tiglitened. To reiliove iiiain ctble assenibly. discotitiect elevis at wheel brake ariii Plaid at liatidbrake connectioii. Fit ncw cahie ass.-nibly and tidjust at cievis a(Ijtisting nut'. eristit'e thztt the loek nul is fuity tiglitene@l after adjtistiiieilt. To remove handbrake lever, disconneet the cable elevis to the lever, remove the two lever securing holts and lift of the handbrake. To fit the handbrake, reverse the above directions. After adjustment of the rear brakes. the handbrake lever sometimes has eccessive free movement. To correct this the following procedure is adopted. Jack up both rear wheels and lock the brakes by means of the adjusters (handbrake off).  Adjust cable length and release the adjusters until the wheels turn freely.

M5

CENTRAL VALVE TYPE MASTER CYLINDER

The master cylinder of the hydraulic brake system consists of an alloy body housing, the inner assembly and a reservoir. The inner assembly is made up of the push rod. dished washer, spring retaining clip, plunger, plunger seal, spring thimble, plunger return spring, valve spacer, spring washer, valve stem and valve seal.

The open end of the cylinder is protected by a rubber dust cover. To remove the master cylinder from the chassis, disconnect the pressure pipe union, split pin, clevis pin and the two bolts securing the master cylinder to the chassis; unscrew the clevis from the push rod.

Dismantling the Master Cylinder

Remove the filler cap and drain off the fluid. Pull back the rubber dust cover and remove the circlip, using a pair of long-nosed pliers.-,. Remove the push rod and dished washer to expose the plunger with seal attached. Remove this assembly complete and separate by lifting the thimble leaf over the shouldered end of the plunger; case the seal off the plunger. Depress the plunger return spring, allowing the valve stem to slide through the elongated hole in the thimble to release the tension spring, remove thimble, spring and valve complete. Detach valve spencer, exercising care with spacer spring washer located under the valve head; remove seal from valve head.

All parts should be carefully examined for wear. damage or distortion and new parts fitted if necessary.

Reassembly of the Master Cylinder

Replace the valve seal with flat side correctly seated against the valve head. Locate the spring washer to the underside of the valve head and hold in position with valve spacer; the spacer legs must face towards the valve seal. Refit the plunger with the return spring positioned centrally on the spacer, insert the thimble in the return spring and depress until the valve stem engages through the thimble elongated hole, checking that the spring is still centrally located on the spacer.

Fit a new plunger seal to the plunger. With the flat of the seal seating against the plunger face insert the reduced end of the plunger into the thimble until the thimble leaf engages under the plunger shoulder, press firmly to locate thimble leaf. 

Smear the assembly with Girling Brake Fluid and position the assembly, valve end first into the cylinder bore, easing the plunger seal lips into the bore. Refit the push rod into the cylinder; ensure that the dished side of the washer is seating under the spherical head. Insert circlip into cylinder bore groove and replace dust cover. Refit the cylinder to the chassis and reconnect to footbrake pedal.

M6

DESCRIPTION OPERATION AND REMOVAL OF THE BRAKES

Front Brakes

Braking is achieved by the action of hydraulically operated pads. housed in a caliper unit, on a disc mounted on the stub axle.

The Girling caliper plate is secured to the stub axle by four bolts and holds the caliper unit and the hydraulic pipe bracket. The caliper unit and the bracket are each secured by two bolts to the plate. The brake disc is secured to the hub by four bolts.

Before removing the caliper unit the wheel must be jacked up and the hydraulic system bled at the bleed valve to release fluid pressure: the pipe line can now be disconnected from the caliper unit.

There is no adjustment on the front brakes, the pads are in constant light contact with the discs and must be renewed when there is insufficient contact or pad thickness. To renew the brake pads, remove the spring pins from the tubular pins retaining the pads and withdraw the tubular pins. Lift out the worn pads and fit new ones, lock in position with tubular pins and spring pins.

Bleeding the Hydraulic System

Bleeding is necessary any time a section of the hydrautic system has been disconnected. or if the level of the brake fluid has been allowed to fail so low  that air has entered the master cylinder. With al the hydraulie connections secure and the supply tank reservoir 'topped-up' with fluid, slaeken off all the brake shoe adjusters where fitted. as far as they will go. Remove the rubber cap from the bleed nipple farthest away from the master cylinder and fit a bleed tube over the bleed nipple. immersing the free end of the tube in brake fluid container in a clean jar.

UNSCREW the bleed nipple approximately threequarters of a turn. Operate the brake pedal with slow flat strokes until the fluid entering the jar is free of air bubbies. lt is advisable to allow two or three seconds pause before every downward stroke. During a down stroke of the brake pedal tighten the bleed nipple, remove the bleed tube and replace the bleed nipple dust cap. Under no circumstance must excessive force be used when tightening the bleed screw.

This process must now be repeated for each bleed nipple at each brake.  Always keep a careful check on the supply tank during bleeding since it is most important that a ffull level is maintained.   Should air reach the master cylinder from the integral supply tank the complete operation of bleeding will have to he repeated. After bleeding, top up the supply tank to its correct level and adjust brakes, as described. Never use the fluid which has been bled from the system to top up the supply tank, because it may have, to some extent become aerated. Fluid which appears dirty or emulsified should he bled from the system and replenished with fresh Girling Crimson Brake Fluid.

Essential Precautions

1 . Use only the genuine Wakefield Girling Brake Fluid (Crimson) obtainable in sealed quart tins.

2. Always ensure extreme cleanliness when dealing with any parts of the hydraulic system. Never handle rubber seals or internal hydraulic parts with greasy hands.

3. Always use clean brake fluid or alcohol when cleaning internal parts of the hydraulic system. On no account should petrol or paraffin be allowed to contact these parts.

4. Examine all seals carefully when overhauling hydraulic cylinders and replace. with genuine Girling spares, any of which shows sings of wear or damage.  Take care not to scratch the highly finished surface of the pistons.

5. Always pack the protective rubber boots in all Girling Master Cylinders, and external wheel cilinders. with Rubber Grease No. 3. obtainable in convenient 2 oz. collapsible tubes from any Girling Agent. (Never use ordinary white brake grease for this purpose.).

6. When a system has heen contaminated with mineral oil, master and wheel cylinders should be wasbed in Clean Brake Fluid or alcohol, and NEW seals and gaskets fitted. The pipelines should be similarly flushed out and rubber hose RENEWED. Reassemble the system and fill with Girting Crimson Brake Fluid. NEVER put dirty fluid back into the reservoir.

Fault locating on Hydraulic Brakes

1.    Pedal travel excessive. Requires pumping.

a.    Brake shoes require adjusting.

b.    Master cylinder push rod requires adjusting (excessive push rod clearance).

2.    Pedal feels springy.

a.    Linings not 'bedded in'.

b.    Brake drums weak or cracked

c.    Master cylinder fixing loose.

3.    Pedal feels spongy. (Does not hold pressure).

a.    Master cylinder cup worn

b.    Master culinder secondary cup worn, air bubbles in supply tank).

c.    Leak at one or more points in system

4.    Brakes inefficient.

a.    Linings not 'bedded in'.

b.    Linings greasy.

c.    Linings incorrect type.

5.    Brakes drag.

a.    Shoes overadjusted.

b.    Shoe pull of springs weak or broken.

c.    Pedal spring weak or broken.

d.    Pedal to push rod adjusmtnet incorrect.

e.    Handbrake mechanisme seized.

f.    Wheel cylinder piston seized.

g.    Supply tank overfilled.

h.    Master cylinder by-pass port choked.

6.    Brakes remain on.

a.    Master cylinder and /or wheel cylinder cups swollen. due to contamination with mineral oil or spurious fluid

b.    Handbrake over-adjustmant

c.    Shoes over-adjusted

d.    Pedal to push rod adjustment incorrect.

7.    Unbalanced braking.

a.    Greasy brakes

b.    Distorted brake drums

c.    Tyres uneventy inflated.

d.    Brake back plate loose on axle.

e.    Worn spring shackles

f.    Different types or grades of linings fitted.

Next pics were not but should have been in the Handbook.  Probably they're not in the handbook because every mecanic knew how to deal with this kind of brakes, that were used in almost all cars of that age 

Thanks Geoff

Thanks James... James Couch provided a "brake excell" click